RE: Pentathlon Kit Build
 

Today I was able to cut the ailerons free from the wings. I capped them with light 3/8" balsa using the new quick drying polyurethane glue (dries white). This stuff activates quickly (Houston humidity) and can be handled in just a couple hours. I sanded the aileron hinge lines and the wing leading edges.



-mark

RE: Pentathlon Kit Build
 

Hi Mark,

what is this new quick drying polyurethane glue you mention??

what's the brand?

I am sheeting and capping black magic cores right at the moment and I may have to run out and get some of that stuff.

thanks, dean

RE: Pentathlon Kit Build
 

The glue comes from Gorilla brand. It is called White Gorilla or something like that. I used it to sheet the rudder and upper/lower fins of my new Pent Kit number 2 for me.

It works fantastic.

Chuck

RE: Pentathlon Kit Build
 

Dean,

Quick Cure Gorilla glue. It has worked for me in the few times that I have used so far...


Regards,
Mark

RE: Pentathlon Kit Build
 

thanks Mark and Chuck for the info.....

I'll swing by Lowes tonight and get some.....

RE: Pentathlon Kit Build
 

The tips have been trimmed and lightly sanded (measure from the root outward at the TE and LE - carefully). The tips are now glued on and sanded flush to the wing and aileron surfaces. Without adding the root rib, I will now set the wing panels aside. The root ribs can be added later when the fuse is framed. This will allow me to fit the wing roots to the form of the fuse side.

-mark

RE: Pentathlon Kit Build
 

With all of the foam core pieces sheeted and finished (except for the wing and stab roots), work can begin on the fuselage frame. The fuse sides should be dry assembled against a straight edge. Once glued together, the 1/16" ply doubler will be laid on the inside surface of its respective fuse side at the nose (do NOT glue) in order to mark where it ends. From this point (right behind the landing gear former) all the way to the tail, we will add some 1/16" balsa doubler material. On my prototype, I sheeted the entire inside surface to the tail (cross-grain). In this build, I will only be placing the 1/16" balsa along the top and bottom edges, and at each former location (vertical slots).



-mark

RE: Pentathlon Kit Build
 

The fuselage frame and formers are built on a flat surface, aligned on top of a straight line. The frame work (known as the fusebox) is built upside down. The fusebox top consists of three pieces that are joined together (small balsa scraps) over the construction line. This is the full length of the fuse, minus the rudder. Secure this to the building surface (tape is fine).

RE: Pentathlon Kit Build
 

I start the former layout with the landing gear area. The front (F4) and rear (F5) formers each have a doubler (F4B, F5B). These will need to be aligned carefully so that the gear plate mates up correctly. With these glued together, check the fit of the gear plate. To get the bottom of the gear plate to sit nice and flush with the bottom of each former, I needed to added a 1/64" shim. I have since changed the laser drawing to account for this. With all three pieces ready, the formers (with doublers and shims already glued on) can be glued into the fusebox top. Once dry, use squares to hold the formers in position while gluing the gear plate in between (epoxy). The bottom of the gear plate needs to be flush with the bottom edge of the formers so that the fusebox bottom will mate to the gear plate without and gap...which would be a major reduction in strength.

RE: Pentathlon Kit Build
 

The rest of the formers can be fitted to the fusebox base and glued in place. Make sure you are putting them in upside down. The firewall can also be glued in place. Notice I used some scrap 1/4"x1/4" balsa to reinforce the joint. A ply ring is also supplied to be used as a blind nut/motor mount support later.

RE: Pentathlon Kit Build
 

The fusebox bottom can now be fitted to the assembly. Dry fit first and make sure this piece fits properly. I used epoxy on the landing gear plate and firewall areas when attaching the fusebox bottom.

The stab doublers can then be glued into the fusebox framework. Again, dry fit and make sure it will go together correctly before applying glue. Make sure the doublers are facing the right direction (notice the rear edge of the doublers end flush with the end of the fusebox).

RE: Pentathlon Kit Build
 

This plane will be using a single elevator servo and a DEPS. Cross braces are included that will properly spread the pushrods in a constant radius from the elev. servo to the tail.

The height of the elevator horn (3/4" long horns will be used) is marked by temporarily placing the stab root rib onto the stab tubes. If using a DEPS, you will have to choose your stab height position now. This can be changed later if using servos in the stabs.

I taped a string in place from the horn position to the approximate elevator servo arm position. Mark the height at which the string passes each former. This is where each DEPS support will be glued.

RE: Pentathlon Kit Build
 

Hey Mark,

Keep it coming, I am storing this all for future reference on my build. It is looking so simple so far that even a duffer like myself should get a solid aircraft out in the end. Perfect!:D

Mark

RE: Pentathlon Kit Build
 

The DEPS and brace assembly (loose) can be placed inside the fusebox frame. Glue each DEPS support on the face of each former at the marked height. The last former will have to be carefully drilled to allow the pushrods to pass through. I was very happy with the end result...very free operation of the pushrods.

RE: Pentathlon Kit Build
 

With the DEPS in place, the fuse sides can be attended to. The balsa sides were completed and set aside earlier. However, before using them, the 1/16" fuse doublers need to be attached to the front end of the fusebox. I used polyurethane glue and secured the ply doublers in place while they cured.

Slots can be marked and cut to allow the fuse sides to fit over the exit points of the DEPS. While dry fitting the fuse sides, pilot holes can be hand drilled thru at the stab tube location. The fuse sides can now be glued on. Near the nose, the fuse sides will have to be clamped while the glue cures.

RE: Pentathlon Kit Build
 

Nice Mark, Your slightly ahead of me. my fuse only has balsa on one side. Glad your doing this, it should minimize my screw ups.

RE: Pentathlon Kit Build
 

Super D...glad the posts help.

With the fuse sides on and dry, the fusebox can be moved from the work table. Inspect all the joints throughout the fusebox. The top and bottom of the fusebox can be block sanded to remove any burrs or little stuff from the tabs, etc.

While I had it on my mind, I put in the antannae (sp?) tube.

RE: Pentathlon Kit Build
 

Now that the fusebox is complete, it can be carefully placed back on the table, over the build line. Without a wing socket handy for the fuse (long story), I began working on the top rear fuse turtle deck. The sheeted core should fit properly from the tailpost up to the top rear deck former (TRD F2). Dry fit TRD F2 and then fit the sheeted deck to that. Please make note of the overall height of the sheeted deck and the top of the TRD F2 former. They should match closely after accounting for sheeting and the 3/8" cap on the top of the sheeted deck. The cutout for the vertical fin can now be made using a small jig included among the laser parts. The jig is simply a guide help quickly get the fit of the vertical fin close, using a dremel tool.

Once the cutout is complete, the sheeted deck can be glued atop the fusebox. I recommend a very ligh amount of polyurethance glue and tape to hold the deck in place.

I mention the wing tube socket above, because this would be the best time to set the wing tube and stab tubes, using the sheeted stabs and wings. Place the fusebox upside down on the build table. Measure carefully (of course) to make sure the distance from tips to a reference point are equal. I try to measure to a corner of the sheeted foam core at each tip, rather than any wood caps that may have been sanded...if the sheeting was carefully sanded flush with the cores, that will be the best place to measure to.

RE: Pentathlon Kit Build
 

More reference for the top rear deck:

I used the inner core for the rear deck to help hold the width just right during the cure cycle of the poly glue. The top of the deck can also be capped with 3/8" (light) balsa sheet.

RE: Pentathlon Kit Build
 

Moving right along....

With the top rear deck glued in place, it might be a good idea to rough sand the top cap now rather than later. The next piece to go on next will protrude higher than the top line of the rear deck....meaning you can't run a sanding bar easily off the front end...

There a two rear deck formers that need to be fitted to meet up with the back end of the canopy. At the top of these, there are two small stringers (very short stringers :) ) that will help set the correct angle for the front former. There is also a base support that will span between the two formers.....this is overkill (I'll talk to the designer) as the tabs in the base of each former only lock into the matching slots on the the fusebox top. With these in place, we can begin work on the canopy.

RE: Pentathlon Kit Build
 

This small section between the two formers can be sheeted using contest grade 3/32" balsa. Use as many planks as necessary to get over the top (small radius).

RE: Pentathlon Kit Build
 

The canopy:

The canopy base, formers, and former supports and be dry fitted. Some of the parts fit very tight, so trim if necessary. If all is a go, then the real assembly can be started on top of the fuselage. By building while on the fuse, we can prevent warping in the base plate and create a good fit to the mating formers for the canopy opening.

Once all of the formers and gussets are secure, 1/8" square balsa stringers can be added. I cut my own stringers for contest grade sheeting...light balsa will make this job easy. Be aware though, do not force the stringers or you can move the formers...especially the front one toward the nose of the fuse. I start on the bottom of one side of the canopy and alternate sides, working toward the top.

RE: Pentathlon Kit Build
 

You will notice, that if applied correctly, the camouflage scheme will come out very nice and bring smiles to young pilots...

oh, and start sheeting the canopy from the bottom up....

RE: Pentathlon Kit Build
 

The canopy sheeting is really not bad. However, the top pieces will take some patience. Wet those sheets and clamp if necessary.

I will final sand and fill the canopy later, when the rest of the fuse top is built.

Tape the canopy in place and begin work on the front deck formers. Use a sheet of wax paper to set the former that mates to the front of the canopy. With the foward front deck former in place (atop the firewall), the stringers can be added.

Sheet this with contest grade 3/32".

RE: Pentathlon Kit Build
 

Went to visit a friend a few nights ago. This one should be really nice when complete.